Torsional decoupler

Abstract

A torsional decoupler comprising a hub having a hub surface, the hub surface having a profile, a pulley having a pulley surface, the pulley surface having a profile, a frictional member disposed between the hub surface and the pulley surface, the frictional member frictionally engaging at least one of the pulley surface or the hub surface, and the frictional member transmitting a torque between the hub and the pulley such that a movement occurs between the hub and the pulley.

1 . A torsional decoupler comprising:
 a hub having a hub surface, the hub surface having a profile;   a pulley having a pulley surface, the pulley surface having a profile;   a frictional member disposed between the hub surface and the pulley surface, the frictional member frictionally engaging at least one of the pulley surface or the hub surface; and   the frictional member transmitting a torque between the hub and the pulley such that a movement occurs between the hub and the pulley.   
     
     
         2 . The torsional decoupler as in  claim 1 , wherein the hub surface comprises a toothed profile. 
     
     
         3 . The torsional decoupler as in  claim 1 , wherein the pulley surface comprises a ribbed profile. 
     
     
         4 . The torsional decoupler as in  claim 1 , wherein the pulley further comprises a surface having a ribbed profile. 
     
     
         5 . The torsional decoupler as in  claim 1 , wherein the frictional member further comprises a plastic material. 
     
     
         6 . The torsional decoupler as in  claim 1 , wherein the frictional member further comprises an elastomeric material. 
     
     
         7 . The torsional decoupler as in  claim 1 , wherein the hub further comprises means for connecting to a shaft. 
     
     
         8 . The torsional decoupler as in  claim 1  further comprising a lock ring engaged to the hub for retaining the pulley and frictional member. 
     
     
         9 . The torsional decoupler as in  claim 1 , wherein the torque transmission magnitude is asymmetric according to the rotational direction. 
     
     
         10 . A torsional decoupler comprising:
 a hub;   a pulley having a surface for engaging a belt;   the hub and the pulley frictionally engaged such that a predetermined amount of micro-slip of the frictional engagement occurs for each rotation of the torsional decoupler.   
     
     
         11 . The torsional decoupler as in  claim 10  further comprising a frictional member disposed between the hub and the pulley, the frictional member having a surface with a profile for engaging the hub. 
     
     
         12 . The torsional decoupler as in  claim 10  further comprising a frictional member disposed between the hub and the pulley, the frictional member having a surface with a profile for engaging the pulley. 
     
     
         13 . The torsional decoupler as in  claim 11 , wherein the profile comprises a toothed profile. 
     
     
         14 . The torsional decoupler as in  claim 12 , wherein the profile comprises a ribbed profile. 
     
     
         15 . The torsional decoupler as in  claim 10 , wherein a torque transmission magnitude is asymmetric according to a rotational direction. 
     
     
         16 . The torsional decoupler as in  claim 10 , wherein the frictional member comprises an elastomeric material. 
     
     
         17 . A torsional decoupler comprising:
 a hub having a hub surface;   a pulley having a pulley surface;   a resilient frictional member disposed between the hub surface and the pulley surface, the resilient frictional member frictionally engaging at least one of the pulley surface or the hub surface; and   the resilient frictional member transmitting a torque between the hub and the pulley such that the transmitted torque magnitude in a first direction is not equal to the transmitted torque magnitude in an opposite direction.   
     
     
         18 . The torsional decoupler as in  claim 17 , wherein the hub surface is toothed and the pulley surface is ribbed. 
     
     
         19 . The torsional decoupler as in  claim 17 , wherein the pulley and the hub are angularly progressable with respect to each other. 
     
     
         20 . The torsional decoupler as in  claim 17 , wherein the hub is engagable with a shaft. 
     
     
         21 . The torsional decoupler as in  claim 17  further comprising:
 a hub assembly comprising a member engaged with the resilient frictional member; and   a torsion spring engaged between the member and the hub.   
     
     
         22 . The torsional decoupler as in  claim 21 , wherein the member comprises a tooth for engaging the resilient frictional member. 
     
     
         23 . The torsional decoupler as in  claim 22 , wherein the hub assembly further comprises a bushing operatively disposed between the member and the hub. 
     
     
         24 . The torsional decoupler as in  claim 17  further comprising a torsion spring connected between the resilient frictional member and the hub.